Problem: Simplify the following expression: ${y-(3y-7)}$
Solution: The minus sign in front of the parentheses means we multiply each term inside the parentheses by ${-1}$ $ y {-1(}\gray{3y-7}{)} $ $ y {-3y+7} $ Combine the $y$ terms: $ {y - 3y} + 7$ $ {-2y} + 7$ The simplified expression is $-2y+7$